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Prologue
Published in Alan Cottrell, An Introduction to Metallurgy, 2019
The study of all effects such as these belongs to the province of physical metallurgy, the part of the subject that deals with the structures of metals and alloys with the aim of designing and producing those structures that give the best properties. Physical metallurgy has obvious links with mechanical metallurgy; but it also has close links with chemical metallurgy, particularly in connection with the casting of metals, the formation of alloys, corrosion, and the many effects of impurities on the structures and properties of metals and alloys. It is the newest part of metallurgy although the processes of quenching and tempering, work-hardening, annealing and alloying were discovered and used, in a completely empirical way, in ancient times. Imaginative attempts to construct a theory of metals, including the essential idea that solid metals might be crystalline, i.e. have their atoms arranged in orderly patterns, were made in the seventeenth and eighteenth centuries. However, there was no way to put these ideas to experimental test in those days and most scientists chose instead to work in fields such as mechanics, astronomy, electricity and chemistry where progress was easier. So the classical pattern of the history of science developed.
Introduction
Published in Gregory N. Haidemenopoulos, Physical Metallurgy, 2018
There is another, equally important, part of metallurgical science, called extractive or chemical metallurgy, which deals with the extraction of the metal from its ore as well as with the processing of the metal in the liquid state (refining, cleaning, deoxidation, alloying). It can be said that chemical metallurgy refines the metal and determines its chemical composition. This is where physical metallurgy starts. Processing to shape the microstructure and achieve the required properties.
Red mud valorization an industrial waste circular economy challenge; review over processes and their chemistry
Published in Critical Reviews in Environmental Science and Technology, 2022
Basudev Swain, Ata Akcil, Jae-chun Lee
The proposed process flowsheet in Figure 16, mainly consists of physical separation, hydrometallurgy, and chemical metallurgy. Worldwide, in the metallurgy industry in general and the Al industry in particular, employs physical separation, hydrometallurgy and chemical metallurgy which already demonstrates cost-effectiveness and also profit-making. As our proposed process employs mainly physical separation and hydrometallurgy processes, process cost-effectiveness is implicated. As far as chemical metallurgy is concern very common chemical which has been being used, hence, can be reasonably considered cost-effective and eco-efficient. Eventually, cost-effectiveness depends upon not only process but also efficiency and metal content at resources. As Figure 16, represents the qualitative process flowsheet, for quantitative recovery and cost-efficient circular economy, all the process parameters need to be optimized, as process parameters greatly affect the efficiencies of recovery. Process parameter involves instrumentation, reactor design, reagent, power, and operational efficiency. Hence, the process parameter like magnetic separation efficiency should be optimized. Similarly, in the leaching and solvent extraction process through minimal use of reagent like lixiviant and extractant the extraction and purification process should be optimized. In the ion exchange process exploring alternative resin and affecting parameters like pH, eluent concentration needed to be optimized.
Discharge stability analysis of top discharge blow tank in dense-phase pneumatic conveying system
Published in Particulate Science and Technology, 2022
Guiling Xu, Qi Zhang, Feihan Chen
Meanwhile, apart from the field of coal gasification, blow tanks are also widely utilized in a variety of industrial fields, such as chemical, metallurgy, medicine and food industries, where their working pressures usually lie in low pressures or atmospheric pressures (Cowell, McGlinchey, and Ansell 2005). In accordance with the material discharge direction, blow tanks are mainly divided into two categories: top discharge blow tanks and bottom discharge blow tanks (Ratnayake et al. 2008). The solid discharge rate, solid-gas ratio and discharge stability belong to three main discharge characteristics of a blow tank, which are greatly affected by operating conditions, powder properties and blow tank structural parameters. To the author’s knowledge, it is rare to investigate the discharge stability for top discharge blow tanks. The knowledge of gas-solid two-phase flow in top discharge blow tanks are still lacking in virtue of the lack of stability analysis. It is still necessary to carry out experimental and theoretical researches on discharge stability of top discharge blow tanks, so as to reveal useful information on the discharge mechanism for this kind of blow tank. In the previous researches of our research group, the effects of operating conditions, powder properties and blow tank structural parameters on solid discharge rate and solid-gas ratio have been systematically investigated in a top discharge blow tank made of plexiglas (Xu et al. 2012, 2013). In this paper, further experimental investigations on discharge stability regarding to solid mass flow rate were implemented.
Copper smelting and converting: past and present Chilean developments
Published in Mineral Processing and Extractive Metallurgy, 2019
Manuel Devia, Roberto Parra, Claudio Queirolo, Mario Sánchez, Igor Wilkomirsky
Developments at the University of Concepcion within the Chemical Metallurgy Group, using a comparative analysis between ferrous and nonferrous metallurgy, have given origin to a new concept of a Smelting-Layer Reactor. Indeed, the Iron and Steel making industry has a structure of production where the material intensity, metallurgical performance and control of their reactors are noticeably higher than the ones from the nonferrous one. Just considering the BOF converter, it is possible to highlight the differences on the rate of reaction and quality control of the products in this refining operation to produce steel from pig iron, compared with the converting and refining reactions and reactors in the nonferrous industry. Basically, for the same objective and even considering that the steel making industry is more challenging than the nonferrous, their results are significantly better. The temperature is without doubt an important factor, with operations on iron and steel at least 300°C higher than the operations on non-ferrous processes. Another key factor is also a much higher interfacial area for the refining reactions that are produced by the supersonic injection of oxygen. Likewise, the development of physicochemical models and thermodynamic databases has allowed an accurate control of the chemical quality of the phases produced (Deo and Boom 1993). The deep knowledge of molten phases characteristics, as well as the capacity to understand and model the physicochemical conditions of the chemical process, allow to control the operation to respond effectively and efficiently to different operational objectives, which vary even from one charge to another.